ExtinctZoo - The Largest Predator To Walk During The Cretaceous Wasn't A Dinosaur?

Episode Date: February 20, 2024

If you to travelled back to North America, anywhere from 83 to 77 million years ago, you would find the lands covered with dinosaurs, many of which were giant. However, they wouldn't be the largest things you could 'run' into, as during those times that largest creature in North America was not a dinosaur, it was a.....

The Cretaceous, a period well known for having produced absolute monsters. It was during this time that the world saw the emergence of not only the largest terrestrial predator ever, but also the largest terrestrial animal to have ever lived. Both of these titans happen to be dinosaurs, which lived on land. But this doesn't mean that the dinosaurs were the only ones who got the privilege to enjoy being massive during the Cretaceous, as many non-dinosaurs also became excessively large, including flying reptiles and marine lizards. Even crocodilians became oversized during this period.

And approximately 82 million years ago in North America, the world witnessed the arrival of the largest crocodilian of all time, the Dinosucas. This Goliath has long been on the radar of paleontologists, as it was first discovered all the way back in the 1850s when large teeth were found in the state of North Carolina. However, the founders of these teeth originally thought them to have belonged to a pliosaur,

and it wasn't until more remains were found, that they understood that their original classification was off. Although, what they did get right from the get-go was that this creature was massive and imposing in real life. Traits that inspired them when naming it as they gave it the name Dinosukas, meaning terrible crocodile. They also gave it the species name Hacherry, and thus Dinosuke's Haceri was born.

With the known remains at the time, they claimed that adult individuals of the species could reach 49 feet or 14.9 meters from snout to tail, while weighing well over 10 tons. This made it unfathomably large, but as the years went by, these estimates were proven to be exaggerations. Though, unlike many species that are first claimed to be huge

and then downsized to relatively normal sizes, the Dinosuchus has actually kept their impressive stature. as new specimens have only confirmed that this truly was a lineage of giant crocodilians, the likes of which has never been seen before. So far, four known species of dynosuchus have been confirmed, which along with the Haccherry include the rugosis, Rio Grandezis, and Tremere. All four are thought to have been giants with Haccherry and Rio Grandezis being the largest. Across the board, paleontologists estimate that the average adult dynosucas

would have been between 8 to 10 meters or 26 to 33 feet while weighing anywhere from 2.5 to 5 tons, making them more than twice the size of a male hippo, and some individuals were able to grow even larger. Currently, the best study large remains have come from the Rio Grandezis species, with some remains appearing to have been 1.5 times larger than the two smaller species, rugosis and chimeri. This has led to paleontologists,

estimating that the biggest Rio Grande, adults could reach a staggering 12 meters or 39 feet in length, while perhaps weighing as much as 8.5 tons, making it heavier than every theropod to have ever existed, minus the tyrant king, that is. At this size, it's also considered to be the largest crocodileian to have ever lived, with only the sarcasucas and the parasaurus coming close. However, the sarcasukas is generally excluded from this debate,

as it wasn't really a crocodile, rather a philetosaur, and is currently thought to have weighed around 5 tons. And the Perosaurus is now generally thought to have been smaller as well, with the absolute largest estimates on the Perosaurus's weight, being around 8.4 tons, making it just a bit smaller. But being the largest crocodilian may not have been enough for the Dinosukas Hacheri, as a few think that the Dinosukas Hacherry got far bigger than its already massive brethren. Specifically, two specimens have been touted as being significantly larger than any individuals found

before, with the highest estimates giving them a length of over 14 meters or 46 feet and a staggering weight of 13 to 14 tons. These numbers, however, have received much scrutiny. And since then, multiple studies have stated that these two specimens have not yet had their sizes fully confirmed, meaning that for now the vast majority of paleontologists cite 39 feet or 12 meters as being the largest possible size for the dino-sukas. This still makes it exceptionally larger than the the largest crocodilian alive today, the saltwater crocodile, which on average is around eight times smaller than the largest dynosuchus. This extreme contrast between the two makes it almost hard to believe that the dynosucous is related to crocodiles, but it indeed is. Although

studies on its brain case have revealed that it's actually more related to another famous crocodile, the alligator, and is a member of the same superfamily, the alligatoroidia. This is one of the three super families that make up the order of crocodilian, and consists of alligators, Caymans, plus any extinct members, more related to alligators than the two other groups. Along with its brain case, the dynosuchus was also surprisingly similar to the alligator in terms of looks, possessing both a body and snout that superficially were alligator-like. An unfortunate occurrence for its victims, as a giant alligator look-alike, would have been quite the terrifying sight. However, besides its general simulmonary,

the dinosaurus was actually very different from other crocs, and sported a skull shape not seen in any living or extinct genus. Additionally, the size of its skull is something rarely seen in any predator, with the biggest ones being around 5.5 feet or 1.7 meters long, about the same length as the skull of an adult spinosaurus. The skull wasn't only big, but also extremely dense and robust, leaving many to believe that it had one hellish bite. but perhaps not as bad as one would think. As in 2002, a study was published that reported a bite force of only 18,000 newtons. This is more than enough to break any bone, but it's still relatively weak for its size, exemplified by the much smaller saltwater crocodile that has a bite force of 16,500 newtons. However, a new study that came out a few years later disagreed with the original estimates

and claimed that this ancient croc had an unfathomably powerful bite, of over 100,000 Newton's, nearly double that of a T-Rex. These two studies give the Dinosuchus one of the widest ranges in bite forces, although there is evidence to suggest that its true bite force lean towards the higher end of this range. Specifically, all of its 22 teeth were extremely robust and built to withstand high forces without breaking, and some even appear to have been highly specialized for demolishing large bones, as those close to the rear of the jaws were short, rounded, and blunt. All this would point to the dinosaurus truly having a massive bite force.

Along with being very durable, the teeth were also quite large, being about the size of a banana. This, along with its body size and bite, has led paleontologists to believe that it may have preyed on the biggest animals around, the dinosaurs. Hadrosaurs in particular are thought to have been a primary source of food for this oversized crock. As several tail vertebrae in Texas belonging to duckbills have bites in them that would match the dynosuchus. These hadrosaurs were likely either the gripposaurus or the cretosaurus. Yet, thanks to the dinosaur's size, they weren't the only ones at risk.

Other dinosaurs, such as a mix of seratops, and ankylosaurus in its environment may not have been safe either. Even large theropods could have been targeted by this menace, as certain bite marks on the Appalachosaurus have been attributed to the dinoosuchus, and it's even thought that this monster actually played a role in theropod's sizes in the area that it inhabited. As scientists have noted that within its eastern range, no theropod came close to it in size, leading to the assumption that it was its region's apex predator. It is thought that the dynosuchus would have employed ambush tactics to capture dinosaurs, and then utilize its crushing power to fatally injure any unfortunate victim.

Furthermore, like modern crocodiles, it is assumed that this Goliath would have been capable of performing the death roll, making it that much more deadly. Fortunately for large dinosaurs, it does seem that certain locations in the U.S. were safe havens from the reign of terror of the Dinosuchus. As particular areas had populations of individuals that were much smaller in stature than normal, likely results of various factors. These smaller dynosucas were more like modern-day alligators in that there were opportunistic feeders and focused on large turtles, fish, and small dinosaurs rather than the larger ones. Another lucky break for its prey came from its growth rate, as it's believed to have been a relatively slow grower. This idea stems from growth rings on its osteoderms, which indicate that individuals took around 35 years to reach full size.

Though, through its long growing period, juveniles were by no means defenseless or harmless, as they were, they were of course still relatively large and retained their formidable bites. Furthermore, all dynosucas also had built in armor via osteoderms, which were bony plates that ran down their backs. These plates were unusually large and heavy, granting them a high level of protection against most attacks from terrestrial and aquatic animals. And the osteoderms didn't stop protection, as they also acted as attachment points for connective tissue, increasing the load-bearing capacity of its body and allowing it to walk fairly efficiently outside of water despite its size. These osteoderms, along with many other useful traits, made the dynosucas one potent killing

machine, and its success is represented by its extensive range, with remains being found throughout the United States and northern Mexico. During its heyday, America was split down the middle by a shallow sea, the western interior seaway. Dinosukas was present on both sides of the seaway, inhabiting 10 different U.S. states. Discovered specimens have shown that it preferred estuaries, which is a partially enclosed coastal body of brackish water, with rivers or streams flowing into it, while having free connection to the open sea.

Besides in estuaries, remains have also been found in what would have been freshwater lakes and rivers, and even marine deposits, meaning that it might have ventured out to the deep parts of the sea and possibly even the ocean. Although, some think these remains were displaced after the animal died. However, if the dynosuchus really did venture to deep waters, then it is plausible that this mighty beast came in a direct contact with some very real sea monsters,

such as the giant mosasaurus of the time, some of which rivaled the dynosuchus in size. Unfortunately for us, no evidence of interactions between the two have been found. Along with mosesors, the dynosuchus' expansive habitat brought it, into contact with a huge range of life, which of course also includes dinosaurs. And among its different environments, it's known to have it coexisted with the Icanocephalus, anodontosaurus, griposaurus, cosmoserotops, nasutoceratops, parasarolophis, Utah serotops, Cretosaurus, Stegoceros, Aguicetopus, Angulomasticator, Aquilorinus, casmosaurus, Edmontonia, euclecephalus, Malefica, Panoplasaurus,

texacephaly, and Yehueca seratops. Other unidentified hadrosaurs, seratops, and ankylosores were also found. Theropods, too, were plentiful in these areas, and included the Sorenethylestis, Richard Oestes, Lephtesia, Lepterinkas, Kirostenotis, hagraphis, Mirarcy, Telos, Territis, Tophonius, Appalachosaurus, and a couple of unidentified Tyrannosaurs. The dynosucas truly lived in an area diverse with dinosaurs, but non-dinosaurus were just as plentiful,

being represented by a variety of turtles, bony fish, cartilaginous fish, invertebrates, snakes, lizards, mosesores, multi-tuberculata, and even marsupials. Unfortunately for all of these animals, they did have to endure the reign of the dynosucas for millions, of years. Yet, their big break would come approximately 73 million years ago when the dynosucas essentially vanished from fossil formations without a trace. Currently, there are no concrete ideas on why it went extinct, and most are skeptical of putting the blame on its size, as there

are many other large animals that fared just fine. Hopefully, though, as more has found out about this crock, we'll find out why it vanished and just how big it truly was.